<!DOCTYPE HTML>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <script type="text/javascript" src="http://libs.baidu.com/jquery/1.9.1/jquery.js"></script>
    <title></title>
</head>
<body>
    <script type="text/javascript">alert($) </script>
</body>
</html>
